Geologic Map of the Ophir Quadrangle, Tooele County, Utah

This map represents the geology of the Ophir quadrangle at 1:24,000 scale. The Ophir quadrangle, in southeastern Tooele County, Utah, includes part of the Oquirrh Mountains and an adjoining part of Rush Valley. Quaternary unconsolidated deposits cover the southwestern two-thirds of the quadrangle, and are broadly divisible into alluvial and lacustrine deposits that are separated by the highstand shoreline of Lake Bonneville. A series of down-to-the-southwest normal faults cut unconsolidated deposits and bedrock parallel to the margin of the Oquirrh Mountains and define the southern Oquirrh Mountain fault zone. Bedrock includes Pennsylvanian-to Cambrian-age sedimentary rocks exposed in the Oquirrh Mountains, which are broadly folded across the north-northwest tranding Ophir anticline. Igneous rocks include rhyolite dikes and other intrusions, and at least two magic dikes that cut across sedimentary bedding and some faults at high angles. This CD includes a 13-page report and two plates.